Tertiary Hydroxyl Acrylate Ink for Bleed-Free Curing

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Solution Overview

Problem

Conventional active-energy-ray-curable inkjet recording methods face issues with ink bleeding and poor drying ability on absorbable recording media, leading to odor concerns and suboptimal curing performance.

Innovation Solution

An active-energy-ray-curable composition containing a (meth)acrylic acid ester compound with a tertiary hydroxyl group, as represented by General Formula (1), which enhances polymerizing ability and curing efficiency while minimizing odor, is developed. This composition includes a multifunctional monomer with two (meth)acrylic acid ester structures and one or two tertiary hydroxyl groups, facilitating cross-linking and improving intermolecular interaction for better curing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional active-energy-ray-curable inkjet recording methods are used, then inkjet recording can be performed, but ink bleeding occurs and drying ability is poor

Engineering Contradiction:
Improvedrying abilityVSAvoidink bleeding
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent changes the chemical parameters of the ink composition by incorporating specific compounds: a multifunctional monomer containing secondary or tertiary hydroxyl groups, a hetero atom-containing polymerizable monomer compound that forms hydrogen bonds with the hydroxyl groups, and a polymerizable isocyanate compound. This chemical composition modification resolves the contradiction by improving drying ability while preventing ink bleeding through enhanced intermolecular interactions and cross-linking.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite ink formulation by combining multiple functional components: the multifunctional monomer (with hydroxyl groups), the hetero atom-containing monomer (forming hydrogen bonds), and the polymerizable isocyanate compound (providing cross-linking). This composite material approach synergistically improves both drying ability and prevents ink bleeding, resolving the technical contradiction between these two properties.

Inventive Principle:
Principle #40Composite materials

2Ease of manufacture

If conventional ink compositions are used, then inkjet recording can be performed, but odor is generated

Engineering Contradiction:
Improveinkjet recording capabilityVSAvoidodor
Core Design Contradiction:
Ease of manufactureVSObject-generated harmful factors

Solution Approach 1:

The patent modifies the chemical composition parameters by selecting specific compounds with lower volatility and odor characteristics. The use of multifunctional monomers with secondary or tertiary hydroxyl groups, combined with hetero atom-containing monomers and polymerizable isocyanate compounds, creates a formulation that maintains inkjet recording capability while significantly reducing odor generation during storage and application.

Inventive Principle:
Principle #35Parameter changes

3Reliability

If conventional ink compositions are used, then inkjet recording can be performed, but active energy ray polymerizing ability and curing ability are suboptimal

Engineering Contradiction:
Improvecuring abilityVSAvoidpolymerizing ability
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent optimizes the chemical parameters of the ink composition by incorporating compounds with specific functional groups that enhance photopolymerization. The multifunctional monomer with secondary or tertiary hydroxyl groups provides multiple polymerization sites, while the hetero atom-containing monomer and polymerizable isocyanate compound contribute to cross-linking density. This composition optimization simultaneously improves both polymerizing ability (speed) and curing ability (final properties) under active energy ray irradiation.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent employs multifunctional monomers that serve multiple roles: they provide hydroxyl groups for hydrogen bonding (improving drying), contain polymerizable groups for cross-linking (improving curing ability), and enable rapid polymerization under active energy rays (improving productivity). This multi-functionality resolves the contradiction between curing ability and polymerizing ability by having a single compound class address both requirements.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The composition achieves excellent active energy ray polymerizing and curing abilities with reduced odor, preventing ink bleeding and enhancing drying efficiency, thus addressing the limitations of conventional methods.

Implementation Method 1

an active-energy-ray-curable composition which contains a (meth)acrylic acid ester compound containing a tertiary hydroxyl group in a molecule of the (meth)acrylic acid ester compound and represented by General Formula (1)

Methodology Applied
Scientific EffectPhotopolymerization: Photopolymerisation

Implementation Method 2

a hetero atom capable of reacting the hydroxyl group with the hetero atom to form a hydrogen bond in a molecular thereof

Methodology Applied
Scientific EffectHydrogen bonding:

Data Source

PatentEP3061795B1Active-energy-ray-curable composition, active-energy-ray-curable ink, composition stored container, two-dimensional or three-dimensional image forming apparatus, method for forming two-dimensional or three-dimensional image, cured material, decorative body, and active energy ray polymerizable compound
Publication Date: 2019.04.24 RICOH CO LTD
  • EP3061795B1 patent drawingFigure 1~2
  • EP3061795B1 patent drawingFigure 3A~3D
  • EP3061795B1 patent drawing

AI summary

An active-energy-ray-curable composition including a (meth)acrylic acid ester compound containing a tertiary hydroxyl group in a molecule of the (meth)acrylic acid ester compound and represented by General Formula (1) below, where in the General Formula (1), OH represents a tertiary hydroxyl group, m and n represent an integer of a range of from 1 through 2, R1 represents a hydrogen atom or a methyl group, and X represents a group formed of an aliphatic hydrocarbon containing from 4 through 10 carbon atoms or a group formed of an aliphatic cyclic hydrocarbon containing from 4 through 10 carbon atoms.